Question

Express sin 81º + tan 81º in terms of trigonometric ratios of angles between 0º and 45º

Answer 1

Hi ,

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We know that ,

i ) sin ( 90 - A ) = cos A

ii ) tan ( 90 - A ) = cot A

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Here ,

sin 81° + tan 81°

= sin( 90 - 9 ) + tan ( 90 - 9 )

= cos 9° + cot 9°


I hope this helps you.

: )